I'm designing the changes required for installing a much deeper, under mount kitchen sink. The difference in height where the tail pipe makes contact with the sink is 7" down from where it is. So one of the things that will need to happen is getting a new sanitary tee installed into the existing pipe, in order to move the drain down. I've opened up the wall where the current tee is, and have some questions for the plumbing pros and semi-pros.
1) There is an elbow at the counter floor level (at the bottom of pic #1), and it feels fairly snug there around the counter framing. So I'm not sure how much this pipe will be willing to drop down. If I can't get pipe to drop down the 1.5" or so that I need to get the new tee in, is there any specialty fitting available to handle something like this? This is a catch-22, because I won't know how much it will move before cutting, and so I would like to be prepared if it doesn't want to move down far enough. I suppose the tie holding the top section could be cut, and attempt to move it up, but don't want to do that unless there is no other choice (don't want to cause new problems on the second floor).
2) I've never done drains, and am just assuming I can copy the existing pipe/trap, giving it the required 1/4 in 12 pitch - any issues with this?
3) The sink will be under mounted to a granite countertop, and I want to get the sink installed (functional) in the exact location I think it should be in, so that they can get their measurements for cutting the countertop precise. But I'm concerned that they may say it needs to be moved forward or backward, and don't want the drain glued and fixed in place so that even 1/2" movement might be impossible. So I was thinking about using a couple of threaded connectors somewhere along the way, in order to make a small adjustment possible. Is this the best way to handle something like this - any better ideas?
4) I could cap the existing tee, or possibly send the dishwasher drain hose into it to make the sink drain simpler, and reduce the possibility of siphon back. I would guess a trap is required for that, along with a dishwasher hose adapter coupling? It seems like that would be a better choice than bringing it into the sink drain as it was originally done (not shown in pic #2). Any problem with 2 close tees like this. There is also a shower on the second floor coming into this line, which would make 3 feeds, but it wouldn't actually be a "new" input that wasn't there previously.
I would appreciate comments from anyone having experience with this stuff, including things that I might be missing that will bite me in a bad place.
1) There is an elbow at the counter floor level (at the bottom of pic #1), and it feels fairly snug there around the counter framing. So I'm not sure how much this pipe will be willing to drop down. If I can't get pipe to drop down the 1.5" or so that I need to get the new tee in, is there any specialty fitting available to handle something like this? This is a catch-22, because I won't know how much it will move before cutting, and so I would like to be prepared if it doesn't want to move down far enough. I suppose the tie holding the top section could be cut, and attempt to move it up, but don't want to do that unless there is no other choice (don't want to cause new problems on the second floor).
2) I've never done drains, and am just assuming I can copy the existing pipe/trap, giving it the required 1/4 in 12 pitch - any issues with this?
3) The sink will be under mounted to a granite countertop, and I want to get the sink installed (functional) in the exact location I think it should be in, so that they can get their measurements for cutting the countertop precise. But I'm concerned that they may say it needs to be moved forward or backward, and don't want the drain glued and fixed in place so that even 1/2" movement might be impossible. So I was thinking about using a couple of threaded connectors somewhere along the way, in order to make a small adjustment possible. Is this the best way to handle something like this - any better ideas?
4) I could cap the existing tee, or possibly send the dishwasher drain hose into it to make the sink drain simpler, and reduce the possibility of siphon back. I would guess a trap is required for that, along with a dishwasher hose adapter coupling? It seems like that would be a better choice than bringing it into the sink drain as it was originally done (not shown in pic #2). Any problem with 2 close tees like this. There is also a shower on the second floor coming into this line, which would make 3 feeds, but it wouldn't actually be a "new" input that wasn't there previously.
I would appreciate comments from anyone having experience with this stuff, including things that I might be missing that will bite me in a bad place.